Shell member and method of manufacture



April 6. 1966 D. R. OSBORN, JR., ETAL 3,248,184

SHELL MEMBER AND METHOD OF MANUFACTURE Filed Jan. 11, 1963 INVENTORS Don R. Osbqrrydn James M. L/vesay PwW Their A f/orn e y sired hole shapes without added operations.

United States Patent 3,248,184 SHELL MEMBER AND NIETHOD OF MANUFACTURE Don R. Osborn, Jr., Dayton, and James M. Livesay,

Brookville, Ohio, assiguors to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed Jan. 11, 1963, Ser. No. 253,236 8 Claims. (Cl. 29-183) The invention relates to a formed shell-like member which may be utilized as a frame or support member for articles cast of a soft material, such as plastic and the method of manufacture of such members. When such members are utilized as reinforcements in plastic parts it is desirable to have holes through which the plastic flows both inside and outside to interlock with the shell.

In the past the manfacture of such shells has been a slow and expensive process. When the shells were formed of blanks they required a series of drawing and forming operations and the holes were usually drilled. If the holes were punched in flat steel, for example, and the drawing operations were then performed, the metal fractured during the draw.

-By use of the invention, shells can be formed from stamped blanks and drawn or otherwise shaped in one operation to form tubular sections and provide the de- Other more complicated sections may be formed, such as hat-like sections as illustrated in the drawing. The blank utlized in making the hat-like section is preferably floriform with openings provided therein about the blank center of such a shape and size that the ribbon sections remaining permit the extreme drawn reductions and depths in a single operation and at the same time provide the desired plastic flow holes.

In the drawing:

FIGURE -1 is a perspective view of a fioreate blank embodying the invention which is provided as a first step in the manufacture of the shell.

FIGURE 2 is a perspective view of a shell formed to a hat-like shape from the blank of FIGURE 1.

FIGURE 3 is a section view with parts broken away and indicating a typical plastic insert construction utilizing the shell of FIGURE 2 as a reinforcement.

The blank 10 may be formed from flat sheet stock. The material may be a metal suitable for the drawing and bendingoperations to which the blank is subjected to provide the finished article. The particular blank illustrated is to be drawn in a single operation so as to provide the hat-like shell 12 shown in FIGURE 2. Shell 12 may be utilized as part of the insert 14 shown in FIGURE 3.

The blank 10 is illustrated as being floreate in conformation and is provided with three areas,'the center area 16 lying generally within the phantom line A, the intermediate generally annular area 18 being between the phantom lines A and B, and the outer annular area 20 lying outside of phantom line B. In the particular construction illustrated, center 16 is solid, while the intermediate area 18 is formed primarily of integral ribbon elements such as arms 22, 24, 26, 28, 30 and 32 which join the center area 16 adjacent the phantom line A. Each of these arms extends generally radially from the center section 16 although various angles may be utilized as desired in order to provide a suitable ultimate struc ture. The outer area 20 is formed of ribbon elements 34, 36, 38, 40, 42 and 44, each of which joins the adjacent outer'ends of two of the arms to provide a petallike configuration. In the particular construction illustrated, arms 28 and 30, for example, are adjacent arms having their outer ends joined by ribbon element 40. The

3,248,184 Patented Apr. 26, 1966 "ice opening 46 defined by these two arms and ribbon element is generally L-shaped with the extreme ends being defined by the inner curved end 48 and the outer curved end 50. The opening legs are defined by the side 52 of arm 28, side 54 of ribbon element 40, and sides 56 and 58 of arm 30 which jointhe curved ends 48 and 50. Sides 56 and 58 of arm 30 meet to provide a point 60 and sides 52 and 54 are joined by a curved section 62 in the area where arm 28 is joined to ribbon elements 38 and 40. Thus the inner leg 64 of opening 46 extends at an angle to a radius from center 16 and the outer leg 66 extends at an opposing angle to a radius from center 16.

The shell 12 is formed by bending the arms of intermediate area 18 so that they extend in an axially parallel direction from the center 16 to provide a generally cylindrical or tubular section 68, and in the same operation bending the ribbon elements forming the outer area 20 substantially at the points where they join the outer ends of the arms so that the ribbon elements each provide a loop extending in a plane at an angle to the generally tubular section 68. In the particular construction illustrated each ribbon element forms a loop by virtue of the fact that the outer ends of the arms are brought together at the end of the tubular section 68 due to the bending of the arms adjacent their inner ends, and the loop openings are provided by the outer legs 66 of openings 46. The operation in which the shell 12 is formed from the blank 10 is preferably a deep draw in which the arms and outer ribbon elements are deformed to provide the desired structure. In the process of the draw, thelpoint 60 of arm 30 is brought close to or into contact with the side 52 of arm 28, as illustrated in FIGURE 2, so that a portion of the opening in leg 64v provides a hole adjacent the center area 16, and another portion of leg 64 together with a portion of opening leg 66 provides another opening area in the tubular section 68.

The hat-like conformation of shell 12 thus has the center 16 and the tubular section 68 providing a crown and the ribbon elements forming the loops providing a brim-like section. In some instances it may be desirable to provide only a tubular section. This may be readily accomplished by utilizing the integral ribbon construction with slightly difierent detailed conformations and draw dies.

The shell12 of FIGURE 2 is illustrated in FIGURE 3 as forming the reinforcement portion of the plastic insert 14. It may be noted that the plastic is cast or otherwise for-med about the insert and is extruded or flowed through the various openings formed from the openings 46 of the blank 10. The shell 12 may also be utilized An article of manufacture and method of making the article has been disclosed utilizing an integral ribbon blank construction which can be drawn to extreme depths in one operation and will provide desired hole shapes without added operations. The blank can be drawn or otherwise formed in this manner without fracturing at a higher production rate than heretofore. Since the process is accomplished by the steps of forming the blank and then reshaping the blank in one operation, the multiple steps of previous constructions are materially reduced.

In the claims:

1. A sheet blank of metal adapted to be deep drawn into a finished hat-shaped support member having at least two right angles on the ouer periphery thereof, said a finished hat-shaped support member having at least two right angles .on the outer periphery thereof, said blank comprising a fiorea-te member having a plurality of generally L-shaped openings radially spaced about the center thereof with the shorter legs of said L-shaped openings being radially inward of the longer legs of said L-shaped openlngs. I

3. The blank of claim 2, each of said L-shaped openings having at least one leg extending at an angle to a radius originating atthe center of said member.

4. The blank of claim 3, each of said L-shaped openings having both the legs thereof extending in opposing angular relation to the radius line originating from the center of said member.

5. A sheet blank of metal adapted to be deep drawn into a finished hat-shaped support member having at least two right angular portions formed by the outer periphery, said hat-shaped support member comprising a generally hat-shaped material supporting member having a plurality of openings therethrough for integral molding with a flowable material, said material supporting member having a crown section formed as a cylinder and a plane section substanially perpendicular to said crown section with said openings extending through both of said sections and defined at least in part by ribbon-like elements.

6. A sheet blank of metal adapted to be deep drawn into a finished hat-shaped support member having at least two right angles on the outer periphery thereof, said blank comprising a center section and a generally annular intermediate section with ribbon arms extending from said center section and a generally annular outer section having ribbon loop elements joining adjacent of said elements,

said arms being bent adjacent said center section to exi tend in axially parallel and circumferentially spaced rea lation at'selected distances from said center section to form a generally tubular section, said outer section loop elements being bent adjacent said intermediate section into a planar conformation substantially perpendicular to said i generally tubular section.

7. The strengthening member of claim 6, said ribbon elements being deformed to define loops extending radially outward from said arms in said planar conformation.

8. The method of forming a hat-shaped metal support member adapted to rigidity a hat-shaped finished plastic member, the steps comprising forming a fioriform perforated blank having angular disposed ribbon arms joined at the center and-the outer ends thereof joined by ribbon elements, and in one continuous operation bending said arms adjacentthe center points to a generally parallel dis- 1 position to form a perforated cylinder section with the outer ribbon arm ends juxtaposed at one end of the, cylinder section and bending the arms at the outer ends so that the ribbon elements form'radially extending loops in a plane at substantially a right angle to the cylinder section.

References Cited by the Examiner UNITED STATES PATENTS 878,299 2/ 1908 Livingstone 29-190 1,266,128 5/1918 Kelly n -473 1,422,636 7/1922 Tomkinson 50-j473 1,689,386 10/1928 Hawkins 1617 2,510,215 6/ 1950 Pityo et al 264--292 2,954,310 9/1960 .Truesdell 161-100 EARL M. BERGERT, Primary Examiner. 

5. A SHEET BLANK OF METAL ADAPTED TO BE DEEP DRAWN INTO A FINISHED HAT-SHAPED SUPPORT MEMBER HAVING AT LEAST TWO RIGHT ANGULAR PORTIONS FORMED BY THE OUTER PERIPHERY, SAID HAT-SHAPED SUPPORT MEMBER COMPRISING A GENERALLY HAT-SHAPED MATERIAL SUPPORTING MEMBER HAVING A PLURALITY OF OPENINGS THERETHROUGH FOR INTERGRAL MOLDING WITH A FLOWABLE MATERIAL, SAID MATERIAL SUPPORTING MEMBER HAVING A CROWN SECTION FORMED AS A CYLINDER AND A PLANE SECTION SUBSTANTIALLY PERPENDICULAR TO SAID CROWN SECTION WITH SAID OPENINGS EXTENDING THROUGH BOTH OF SAID SECTIONS AND DEFINED AT LEAST IN PART BY RIBBON-LIKE ELEMENTS. 